The Sleepwalker

Lars Kepler is the pseudonym of critically acclaimed husband and wife team Alexandra Coelho Ahndoril (b. 1966) and Alexander Ahndoril (b. 1967), authors of the No. 1 internationally bestselling Joona Linna series.

With seven instalments to date, the series has sold 15 million copies in 40 languages. The Ahndorils were both established writers before they adopted the pen name Lars Kepler, and have each published several acclaimed novels.